I'm new to this pea but I suppose you're correct ---instead of pushing through the hair , by using this motion you are slicing as well as pushing ---all I know is on the against the grain pass, the results were dramatic for me. Usually when I try the third pass, the razor skips, bumps, and digs in if I use a straight push through ---but with the scything motion and pivoting slightly around the tang/scale pin, the razor seems more stable (maybe being anchored around the pivot point) and I was successful and --well --encouraged.